I think it's safe to say that te mentioned package is not compatible with version 6.1.6 of Umbraco.

In the description of the package it states that it works with Umbraco 4x and the package was released in 2010. A lot has happened in the world of Umbraco ever since so I'm convinced that the reason you get an error is simply that it unfortunately does not work with your version.

Besides even though the idea of automatic translation of a text into multiple other languages is cool I'm not sure it's the best approach when dealing with real texts on a real website since the translations won't be accurate and create confusion among the visitors who might not trust the website and therefore won't buy anything for instance.

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